In times of national crisis, the Supreme Court can get very flexible without even admitting to a change of standards. (See, e.g., Korematsu v. United States (1944) 323 U.S. 214.)
I'm afraid to look. That was FDR's packed court era.
That wasn't the case where Hugo Black developed his creative interpretation on how the 14th incorporated the Bill of Rights - but only some, at that, is it?